Along the east wall of my apartment, I have two bookshelves pressed against each other: a 4×4 Expedit unit, and a 2×4 Expedit unit, from IKEA. However, as shelf space runs low, I am considering stacking the 2×4 on top of the 4×4. That way, I can add another 2×4 unit along the side, and I will gain an additional sixteen cubes of shelf space.

So, basically, what I have now kind of looks like this:

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But I want to make it look like this:

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So that after adding another unit, it will come out looking like this:

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Make sense?

I’ve seen some photos of Expedit units that simply look stacked one upon the other, and others that appear as if they’re been anchored to the wall. It’s my guess that simply stacking a 2×4 on top of a 4×4 will provide enough weight to hold the unit there, but I’d like to find someone to actually tell me: “Yeah, I stacked my Expedits five years ago and the fuckers haven’t moved an inch” before I risk it myself.

FYI: while they can sometimes be a tremendous pain-in-the-ass to put together, I love IKEA’s Expedit units — they look clean and modern, they’re easy to clean, and they hold a lot of books or media.